In the hot seat since the Sept. 9 rupture of one of its natural gas transmission pipelines, Pacific Gas and Electric Co. (PG&E) sent a nine-member engineering team to the three-day National Transportation Safety Board (NTSB) hearings, which began Tuesday in Washington, DC.
Focus returned to familiar issues such the lack of automatic valves on the ruptured pipe segment, a control room electrical surge that affected pressure regulators and inaccuracies in PG&E records.
Both the San Francisco-based combination utility and the pipeline industry released statements of support for the ongoing NTSB work to identify the root cause of the pipeline failure in San Bruno, CA, that killed eight people and leveled parts of a quiet suburban neighborhood last year.
With San Bruno's mayor and a city council member in attendance, along with the PG&E utility's president, federal investigators asked detailed questions of the PG&E team, headed by Edward Salas, senior vice president for engineering and operations. Some questioning centered on a senior gas engineer's analysis five years ago that rejected the need for automatic shutoff valves on the pipeline that ruptured.
In addition to the San Francisco suburb's officials, other panels of witnesses expected to ask questions and be questioned during the hearings included the California Public Utilities Commission, NTSB's Pipeline and Hazardous Materials Safety Administration (PHMSA), and the International Brotherhood of Electric Workers Local 1245.
While saying it expects NTSB's ongoing investigation to provide "important insights" into the tragic pipeline explosion and fire (see Daily GPI, Sept. 13, 2010), PG&E said it has been making pipeline safety changes -- "not waiting for mandates from legislators or regulators." It is thoroughly evaluating procedures and policies related to its pipeline system's operations, maintenance and integrity management programs, a utility spokesperson said as the NTSB hearings began.
Separately, the pipeline trade group the Interstate Natural Gas Association of America (INGAA) on Tuesday adopted a set of guiding principles for pipeline safety. INGAA said they were expected to renew the industry's "commitment to safe and reliable pipeline operations."
INGAA CEO Don Santa called the guiding principles a first step and said a "board-level task force" will follow up to identify specific tasks for achieving each of the principles and establishing a timeline for completing the tasks. "Our goal is zero incidents. Right now we don't have a perfect record, but we are committed to that goal."
Going into extreme technical details, NTSB staff peppered at least two panels of PG&E engineers with questions about pipeline pressures, testing of lines for their ability to withstand the operating pressures, and how in regard to Line 132 in general and its failed segment in particular, the utility was addressing integrity management, risks and manufacturers' defects in advance of last year's incident.
NTSB Chairman Deborah Hersman kicked off the hearing by reiterating that the federal agency was using the three days of hearings to deepen its investigators' knowledge of PG&E's pipeline system and related operations. PG&E's Salas underscored that the utility is now more focused on high consequence areas (HCA) and in streamlining and expanding its record keeping.
Faulty records caused NTSB to take a fairly unprecedented step earlier this year in issuing an interim report and recommendations related to all transmission pipelines operating nationally. The federal investigators took time to call out the fact that it thought record keeping and the basis for operating pressures in large pipelines in some instances are inadequate and more attention was needed nationally (see Daily GPI, Jan. 14).
For the future, PG&E engineers told NTSB questioners that they are working on the development of a high-resolution camera that could be used in internal (in-line) scans of pipe segments at the same time operating pressures were tested on any given line. Currently a lot of the PG&E system is not capable of being tested internally with in-line technology, utility engineers told the federal investigators. More broadly, the utility representatives said a total modernization of its pipeline operating and maintenance system is under way.
©Copyright 2011 Intelligence Press Inc. All rights reserved. The preceding news report may not be republished or redistributed, in whole or in part, in any form, without prior written consent of Intelligence Press, Inc.